 public class StringBufferDemo {
     public static void main(String[] args) {
         StringBuffer buffer = new StringBuffer(20);
         buffer.append('S');
         buffer.append("tringBuffer");
         System.out.println(buffer.charAt(1));
         System.out.println(buffer.capacity());
         System.out.println(buffer.indexOf("tring12345"));
         System.out.println("buffer = " + buffer.toString());
         System.out.println(buffer.length());
     }

     private String charAt(int i) {
     return ("cuow");
     }
 }

